The present invention relates generally to implants for the body and particularly to implants that have features that minimize or prevent rotation of an implant in a body. More specifically, the present invention is a breast implant that has an anatomical shape that gives a more natural look to the augmented breast, but cannot rotate because it has a texturing on the back that anchors it, yet is smooth on the surface to minimize rippling.
The preferred shape for an implant used for cosmetic breast augmentation is the so-called “anatomical shape” that is also referred to as “tear drop.” This shape has more of the substance filling the silicone elastomer shell in the inferior pole of the implant and less in the superior pole, thus mimicking the natural shape of the breast. For a given volume, round shaped implants have too much substance in the upper pole that can make the breast look artificial. The anatomical implant looks much more natural.
A problem with anatomical implants is that if the outer surface of the implant is smooth, the implant can rotate. When an implant is surgically placed beneath the breast or beneath the chest muscle, the body recognizes that it is a foreign object and walls it off with tissue that is referred to as a “capsule.” A smooth-walled implant creates a smooth capsule that can allow the implant to slip and slide within it. When a smooth-walled anatomical-shaped breast implant rotates, as it often does, there is more fullness laterally or medially instead of inferiorally as intended. This creates an unacceptable deformity. Thus far the only solution to this problem has been the use of “textured” implants which have a rough surface. They produce a capsule that is reciprocally rough. The “male-female” relationship of the implant and capsule holds the implant in place and prevents its rotation.
Textured implants have a very distinct disadvantage, however. The problem is that textured implants have a tendency to ripple (i.e. produce a folding, wrinkling or waviness on the surface of the implant). Rippling creates an extremely unsatisfactory appearance. Causes of or factors contributing to rippling may be 1) that textured implants are cured twice, while smooth walled implants are cured once, 2) that the textured implant is formed with an additional coating of the silicone elastomer, leading to a thicker wall that is less able to support itself and thus may fold, and/or 3) the texture itself (peaks and valleys in the surface of the implant) may produce a variety of non-linear scores or fold lines along which the wall of the implant folds or ripples.
Rippling—visible or palpable waviness on the implant surface—is one of the major problems with breast implants. This folding of the implant can often be felt or seen and can be extremely obtrusive. Therefore, to solve the problem of implant rotation with texturing the entire implant as is presently done, one must compound the problem of severe, unacceptable rippling.
The present invention provides a solution to the problem. The present invention is an implant that is textured on its posterior surface, but smooth on its anterior surface. The textured posterior surface causes a reciprocal textured capsule, but only behind the implant. This interlocking with the capsule keeps the implant from rotating. However, the textured area is only on the back of the implant; therefore, any rippling will not be visible or palpable. The anterior surface will remain smooth—and minimize any unsatisfactory rippling.
Preferred fill materials for the non-rotating anatomical-shaped breast implant include saline and viscous fill materials. Among viscous fill materials, silicone gel, soy oil, and hydrogels are preferred, with hydrogels being most preferred.